Pipe wrench



I c. G. MINOR Jan. 3, 1939.

' PIPE WRENCH Filed Sept. 5, 1935 3 Shee ts-Sheet l INVENTOR.

ATTORNEY.

C. G. MINOR PIPE WRENCH Jah. 3, 1939.

' s Sheets-Sheet 2 Filed Sept. 3, 1935 I INVENTOR. fla z/es.5%0koz ATTORNEY.

Jan. 3, 1939. I c. G. MINOR 2,142,696

PIPE WRENCH Filed Sept. 5, 1935 s Sheets-Sheet s INVENTOR.

' Kiev/e527. i z'zzaz" ATTORNEY.

Patented Jan. 3, 1939 UNHTED STATES This invention relates to improvements in pipe wrenches of the type including a fixed and a movable jaw pivotally connected by non-parallel links.

The principal object of the invention is to provide means whereby wrenches of this type may be adjusted to a plurality of positions which will accommodate a plurality of sizes of pipe in each position of adjustment.

A further object of the inventionis to provide an adjustable self-tightening wrench that will accommodate a plurality of sizes of pipe in each position of adjustment and will deliver a substantially uniform squeeze or bite in each position of adjustment.

A further object of the invention is to provide improved means for normally retaining the jaws in open position with the movable jaw urged forwardly away from the handle.

Another object of the invention is the provision in an adjustable wrench of means for tightening the grip of the wrench automatically as the jaw handle is turned.

Other objects and advantages of the invention will become apparent as'the description progresses, taken in conjunction with the accompanying drawings wherein,

Fig. 1 is a side elevation of a wrench embodying the invention, having a portion of a link broken away to show certain details of the invention.

Fig. 2 is a similar view on a smaller scale, illustrating adjustment of the wrench for larger size pipes.

Fig. 3 is a side elevation of a modified form of wrench illustrating another embodiment of my invention, one of the links having a portion broken away to show certain details of construction, the wrench being adjusted to accommodate large size pipes.

Fig. 4 is a view similar to Fig. 3 showing said modified form of wrench in position to accommodate pipes smaller than those which the adjustment shown in Fig. 3 will accommodate.

Fig. 5 is a view similar to Figs. 3 and 4, showing said wrench in position to accommodate still smaller pipes than can be accommodated by the adjustment shown in Fig. 4, and

Fig. 6 is a side elevation of a wrench illustrating another embodiment of my invention, a portion of the link being broken. away to show certain details of construction, from which it may be seen that a plurality of adjustments, such as shown in Figs. 3, 4, and 5 may be made.

Referring to the drawings, the reference num- PATENT QEFEE PIPE. WRENCH Charles G. Minor, Detroit, Mich.

Application September 3, 1935, Serial No. 38,886

7 Claims. (0]. 81-117) eral Ill denotes a suitable handleportion, one end 7:

of which is formed into a fixed jaw l l. Coacting with the fixed jaw is a movable jaw l2. Each of the jaws are provided with angular and oppositely disposed teeth 3, arranged in the usual manner for the purpose of tightly gripping a pipe or other object. The jaws H and :2 are swingingly connected by non-parallel links M and IS, the link l4 being of greater length than the link 15. Preferably the pivotal points on. the movable jaw are closer together than the pivotal points on the fixed jaw in order to assure a tight gripping action on the pipe P on movement of the handle H1 in the direction of the arrow shown in Fig. 1.

Many previous wrenches have been made in an attempt to make a wrench which is adjustable to a plurality of positions and is self-tightening and which will accommodate a plurality of sizes of pipe in each position of adjustment, all of which have been impractical and have failed on the commercial market because they did not embody the correct principles.

In order to have a self-tightening wrench of this type operate in each of its positions of adjustment, the following features must be embodied in the design:

(a) The pivot points on the jaw carrying the handle must have a uniform distance between them regardless of the position of adjustment.

(1)) The pivot points on the movable jaw must have a uniform distance between them regardless of the position of adjustment.

(0) The adjustable means must permit a tightening of the jaws at the outer ends where the teeth grip the pipe, on turning of the wrench.

In my preferred embodiment, as shown in Figs. 1 and 2, I make the link i4 U-shaped, mounting the legs of the U to the fixed jaw by any suitable means, such as by the pivot pin l6 and I provide adjustable means for contacting a fixed point in the movable jaw.

In Figs. 1 and 2 I show the connecting cross portion I! of the link l4 provided with three spaced pins I 8, I9, and 20 respectively, and the movable jaw I2 is shown as provided with an upset portion 2i having a notch 22 therein adapted to engage any one of said pins. In lieu of the pins shown, said connecting portion may be made with integral lugs or in any other suitable manner, serving the same purpose.

In said preferred embodiment, as shown in Figs. 1 and 2, the connecting portion ll of said U-shaped link I4 is of arcuate outline in cross section and inclines in such manner that pin I3 is closer to pivot member it than either pin [9 or 20 and pin I9 is closer to the pivot member I6 than is pin 20.

In all embodiments of my invention, the rear link or yoke I5 is preferably composed of a pair of similar link members I5a, only one of which is shown in the drawings, the same being pivoted on opposite sides of the fixed jaw at 23 and pivoted on opposite sides of the movable jaw as at 24.

In order to maintain the jaws normally separated so as to retain the link I4 in position and with the movable jaw urged forwardly away from the handle, I provide a leaf spring 25. This spring 25 has one end bent up behind the rear end of movable jaw I2 and has its other end slideably engaging the inner surface of jaw I2, said surface being preferably inclined, as shown in the drawings. I secure said spring to jaw II by a screw 26 or other suitable means. It is evident that one end of this spring keeps the jaws apart and that the other end urges jaw I2 forwardly: away from the handle iii to a definite stop 28, the rearward movement of the link I5 being limited by stop 21.

In the modification of my invention as shown in Figs. 3, 4, and 5, I have shown the yoke ad.- jacent the teeth as being composed of a pair of similar link members Ma pivotally connected to jaw II in the same manner that yoke I4 is connected thereto in the preferred embodiment, and having their other ends pivotally connected by pivot member Ila.

On this pivot member Ila is pivotally mounted a cam member 35 of general triangular outline and having three externally projecting arcuate surfaces 3i, 32, and 33, surface 3| being the farthest offset from pivot member Ila, surface 32 being a little closer to said pivot member and surface 3| being closest thereto.

In the jaw I2 I provide a cam groove or notch 34 which is adapted to receive any one of said arcuate surfaces 3|, 32, or 33 of said cam membar.

In Fig. 6, in lieu of the cam member 30, I provide an eccentric member 40, having four projecting members 4!, 42, 43, and 44, projection 4| being the farthest offset from the pivot member Ila, projections 42 and 43 being closer thereto and projection 44 being closest thereto. In this modification, the receiving groove 45 in jaw I4 is made in form to fit any one of said projections of the eccentric.

The wrench, as illustrated in any of the forms shown is capable of handling at least three sizes of pipe in any one of its three positions of adjustment. In Fig. 1, for instance, one may readily see that a smaller pipe may be gripped by the jaws by simply pushing the smaller pipe further into the jaws.

After this wrench has been adjusted to the desired spaced distance of the jaws, it may be operated with one hand, the operator simply putting the jaws over a pipe and pushing or pulling the handle in the direction of the arrow shown in Fig. 1. Before the wrench tightens upon the pipe, it makes contact as shown in dotted lines in Figs. 3, 4, 5 and 6. As the handle is turned, the wrench tightens, causing the relative position of the two jaws to take the position shown in full lines.

In other words, the tightening action causes the teeth of the respective jaws to come closer together while the rear of the movable jaw assumes a lower position relative to the rear of the upper jaw and the entire lower jaw assumes a position to the rear of that which it first occupied in relation to the upper jaw.

The points of the teeth are set on each jaw in such manner as to give an angular opening for the pipes to be gripped thereby. The degree of angularity of said points of the teeth must be worked out geometrically for the sizes of the pipes contemplated to be handled by each wrench. For instance, if it is desired to make a wrench that will handle pipes of one-half inch, threequarter inch and one inch diameters respectively, when the wrench is in position for the shortest distance between the teeth, the included angle of the points of the teeth must be designed differently than when pipes of different dimensions are to be handled. Any other pipes coming within the included angle may, however, be handled by the wrench when the jaws are spaced further apart by the adjustable means.

The structure herein described enables the center of the fulcrum point connection between the yoke and the movable jaw to operate or move through an arc of a circle struck from the link end fulcrum point of the movable jaw and passing through a direct center line drawn perpendicular to the center line of the wrench handle.

Having thus fully described my invention, I do not wish to be limited to the exact forms of my wrench illustrated in the drawings and herein described, as it is evident to one skilled in the art that many modifications thereof may be made which fall within the scope of the appended claims.

I claim:

1. An adjustable self-tightening wrench comprising a jaw carrying a handle, a movable jaw, a notch on the outer edge of one jaw, a link engaging said one jaw and pivoted to the other, said link having a plurality of means for selectively engaging said notch when the jaws are spaced in any one of a number of predetermined adjustable positions, spring means for keeping the jaws apart and for urging the movable jaw forwardly in relation to the other, a shorter link pivoted to the jaws in rear of the first named link and at an angle thereto, teeth on the handled jaw inclined toward the handle, and oppositely disposed teeth on the movable jaw.

2. An adjustable self-tightening wrench comprising a jaw carrying a handle, a movable jaw, a U-shaped link pivoted to the fixed jaw and embracing the movable jaw, said movable jaw having a seat on the outer edge thereof and said link having a plurality of means for selectively engaging said seat whereby to pivotally connect said link with said movable jaw in any one of a plurality of predetermined positions, spring means for keeping the jaws apart and for urging the movable jaw forwardly in relation to the other jaw, a shorter link pivoted to the jaws in rear of and at an angle to the first named link whereby said links incline toward each other from their pivot points on the handled jaw, teeth on the handled jaw inclined toward the handle, and oppositely disposed teeth on the movable aw.

3. An adjustable self-tightening wrench comprising a jaw carrying a handle, a movable jaw, a notch on the outer edge of one jaw, a U-shaped link embracing said jaw and pivoted to the other, said link having a plurality of spaced members any one of which is adapted to be received in said notch for the purpose of adjusting the opening of said jaws, spring means for keeping the jaws apart and for urging the movable jaw forwardly "I6 in relation to the other, a shorter link pivoted to the jaws in rear of and at an angle to the first named link, teeth on the handled jaw inclined toward the handle, and oppositely disposed teeth on the movable jaw.

4. An adjustable self-tightening wrench comprising a jaw carrying a handle, a movable jaw, a link comprising a pair of similar link arms pivotally mounted on the jaw carrying the handle and provided with a cross member uniting the other ends of said arms, a cam member pivotally mounted on said cross member and provided with a plurality of surfaces of unequal distance from said cross member, a seat on the outer edge of said movable jaw adapted to engage any one of said plurality of surfaces of said cam member, spring means for keeping the jaws apart and for urging the movable jaw forwardly in relation to the other jaw, a shorter link pivoted to the jaws in rear of and at an angle to the first named link whereby said links incline toward each other from their pivot points on the handled jaw, teeth on the handled jaw inclined toward the handle, and oppositely disposed teeth on the movable jaw.

5. An adjustable self-tightening wrench comprising a jaw carrying a handle, a movable jaw, a notch on the outer edge of one jaw, a link engaging said one jaw and pivoted to the other, said link having a plurality of fixedly mounted means for selectively engaging said notch when the jaws are spaced in any one of a number of predetermined adjustable positions, spring means for keeping the jaws apart and for urging the movable jaw forwardly in relation to the other, a shorter link pivoted to the jaws in rear of the first named link and at an angle thereto, teeth on the handled jaw inclined toward the handle, and oppositely disposed teeth on the movable 6. An adjustable self-tightening wrench comprising a jaw carrying a handle, a movable jaw, a notch on the outer edge of one jaw, a link engaging said one jaw and pivoted to the other, said link having a plurality of means for selectively engaging said notch when the jaws are spaced in any one of a number of predetermined adjustable positions, spring means for keeping the jaws apart and for urging the movable jaw forwardly in relation to the other, a shorter link pivoted to the jaws in rear of the first named link and at an angle thereto, the said jaws and links being so arranged that as the various adjustments are made the center of the pivotal point connection between the first mentioned link and the movable jaw will move through an are from the center of the pivotal point of the movable jaw and the shorter link and passing through a direct center line drawn perpendicular to the center line of the wrench handle, and gripping means on the outer ends of said jaws.

7. An adjustable self-tightening wrench comprising a jaw carrying a handle, a movable jaw, said wrench having opposing clamping faces at one end thereof, a link pivotally connecting said jaws adjacent to said faces and extending approximately at right angles to the relative movement of said jaws, a second link pivotally connected to said handle-carrying jaw at a point remote from said faces extending in a direction inclined to the perpendicular to the relative movement of said jaws and pivoted to said movable jaw, the first named link being adjustable as to the distance between its pivots without altering its relative angular position whereby the distance apart of said jaws is determined.

CHARLES G. MINOR. 

